The present invention relates to the preparation of pastas and more particularly to the preparation of pre-cooked, shelf-stable or refrigerated, acidified pasta products.
Traditionally, shelf-stable or refrigerated pre-cooked/acidified pastas are prepared by boiling pastas (raw/wet or dried) in acidified water, coating with oil followed by packaging and heat processing with steam or boiling water (for example, a product temperature of 90.degree.-95.degree. C. for about 10-20 minutes). In some cases, the pasta products are sterilized at higher temperatures (for example 104.degree. C.) using a shorter processing time. Various kinds of acids and combinants are used in the pasta acidification process to obtain a pH of the pastas below 4.6 and a low acid taste. Although this boiling-in-acidified water process is the quickest way to cook and acidify pastas, it has some drawbacks.
1) Firstly, cooking pasta in boiling water has a cooking loss problem, especially if the temperature of boiling water is not high enough (for example, not above 97.degree. C.) and this results in poor pasta texture. Controlling the cooking water temperature is difficult because it is related to the amount and temperature of the pasta cooked. PA0 2) Secondly, continuous cooking of pastas in the same acidified water requires constant feeding of fresh water and acid and this is not only cumbersome, but it also requires constant monitoring of water acidity. PA0 a) by spraying the water onto the pasta or immersing the pasta in the water followed by packaging and heat processing or PA0 b) by placing the pasta in a package, adding the water to the pasta in the package and then heat processing. This water addition to the twice steamed pasta followed by heat processing can enable the production of a cooked pasta with a moisture content of from 50 to 70% by weight regardless of the pasta thickness and the water absorption property.
In recent years, there have been patented several processes in which it has been tried to eliminate the acidic boiling process and utilize the final healing step for acidification (post-packaging heating, so called in-pack-pasteurization) which is commonly used in pre-cooked/acidified pasta processes for pasta cooking. For example, U.S. Pat. No. 4,734,291 describes a process which does not use acidified water boiling for pasta cooking, but instead, regular raw/wet pastas are steamed first to give partially cooked pastas, then a certain amount of acidic water is added to the partially cooked pastas, which are finally packaged and heat processed (equivalent to 104.degree. C. for about 10 minutes). U.S. Pat. No. 5,057,330 describes a process in which pastas are cooked by boiling but not in acidic water, after which a certain mount of acidic water is added to the pastas which are finally packaged and heat processed and wherein alkaline neutralizing agents such as sodium bicarbonate are provided to neutralize the acid taste during consumption.
The above-mentioned patents describe processes which attempt to eliminate or reduce the cumbersome process of cooking pastas in acidic water. Ideally, direct acidification of a pasta dough without any further acidification step needed is desirable. For example, U.S. Pat. No. 4,597,976 describes a process using direct addition of acids to the pasta dough which is then formed into pasta shapes by either extrusion or sheeting/slitting, the extruded or sheeted/slitted, raw, wet or dried, acidified pastas are then cooked in regular water, the cooked pastas are then steamed to a temperature of at least 85.degree. C., then packaged with acidified sauce and heat processed again under conditions equivalent to about 10 minutes at 93.degree. C. Although in this process the pastas are not cooked in acidic water, a water boiling step is still used. Also, in this process the raw/wet pastas are not steamed first before boiling in order to prevent leaching of pasta starch and acid, and the absence of this steaming step, therefore, results in a reduction of pasta acidity as well as poor cooked pasta texture. There is a need for a simple process involving direct acidification of pasta dough while also retaining cooked pasta acidity and good texture.